Do guys mirror girls when they like them?

For example like if they change their bio on Instagram to like "I like taking pictures of the sunset" and like a week later he starts posting pictures of like sunsets and stuff (he still does it till this day) . What does it mean?

That's strange. It's one thing to imitate people you look up to and another to imitate a crush or partner. Wait, I take that back. Some people do imitate their crush to a degree. For example the crush might say a line or do a certain thing and the person who is crushing notices and does the same thing. To answer your question, he is looking at your social media and he takes notice to what you like.